Effects on mouse embryos of in utero exposure to saccharin: teratogenic and chromosome effects

The genotoxic and teratogenic effects of maltitol in rats

In the present study, the genotoxic and cytotoxic effects of the low-caloric artificial sweetener maltitol, which is a sugar alcohol (polyol), were investigated in the bone marrow cells of rats using the chromosome aberration (CA) test. In addition, the teratogenicity and embryotoxicity of maltitol was also investigated in rats. To reveal the genotoxicity and cytotoxicity of maltitol, rats were intraperitoneally administered 2.5, 5 and 10 g/kg body weight (bw) concentrations of maltitol for 6, 12 and 24 h treatment period. The pregnant females were intraperitoneally treated with 1, 2 and 4 g/kg bw/day concentrations of maltitol during the first 7 days of gestation (first trimester) to investigate the teratogenicity of maltitol. The embryos were collected after killing the dams by cervical dislocation under ether anaesthesia on gestation day 19. Maltitol did not induce the CA and did not decrease the mitotic index in bone marrow cells of rats at all concentrations and treatment periods. In addition, maltitol was not teratogenic; however, it decreased the foetuses weight and at the highest dose (4 g/kg bw) caused growth retardation.

Quantitative Extrapolation of In Vitro Whole Embryo Culture Embryotoxicity Data to Developmental Toxicity In Vivo Using the Benchmark Dose Approach

If in vitro data are to be used as a basis for hazard characterization, a translation of an in vitro concentration toward an in vivo dose must be made. In this study we examined the correlation between dose descriptors from the in vitro Whole Embryo Culture (WEC) test and in vivo developmental toxicity tests. We applied the Benchmark Dose (BMD) approach to estimate equipotent in vitro concentrations (Benchmark Concentrations [BMCs]) and equipotent in vivo doses (BMDs). Using the data generated in an European Center for the Validation of Alternative Methods validation study we found that the BMCs were highly reproducible among laboratories. The three endpoints analyzed (head length, crown-rump length, and total morphological score) were strongly correlated. A clear in vitro-in vivo correlation was found between BMCs and BMDs. However, a considerable uncertainty would remain if the BMDs were estimated from the BMC using this correlation: the confidence interval of such an in vivo dose estimate would span various orders of magnitude. Differences in toxicokinetic properties among the compounds explained at least part of the scatter of the in vitro-in vivo correlation. But also heterogeneity in the design of the available in vivo studies underlies much of the scatter, and this puts a limit on validating in vitro data as predictors of in vivo data. Further analysis of the in vitro-in vivo correlation would therefore require high-quality in vivo data, generated by appropriate (and similar) study designs.